title: Primary and secondary structure of U2 snRNA.
abstract: With the improved rapid sequencing techniques, the earlier sequence of U2 RNA of Novikoff hepatoma (Shibata et al, J. Biol. Chem. 250, 3909-3920, 1975) was reanalyzed and modified. The improved sequence of U2 RNA is 188 (or 189) nucleotides long and is in register with a characterized U2 RNA pseudogene (Denison et al, PNAS 78, 810-814, 1981) except for an 11 nucleotide sequence (nucleotides 147-157) which is absent from the pseudogene. From these results, a secondary structure of U2 RNA is proposed which is supported by the preferred cleavage sites with T1-RNase, RNase A and S1 nuclease. Isolated U2 RNA was cleaved by T1-RNase preferentially at positions 64 and 164, whereas U2 RNA in U2-snRNP was cleaved only at position 64, indicating that position 164 is protected in U2-snRNP. As with U1 RNA (Epstein et al, PNAS 78, 1562-1566, 1981) the 5'-end of isolated U2 RNA was not preferentially cleaved by T1-RNase.
mesh_terms: D000818:Animals; D001483:Base Sequence; D008114:Liver Neoplasms, Experimental / Q000032:analysis; D009690:Nucleic Acid Conformation; D009843:Oligoribonucleotides / Q000032:analysis; D012334:RNA, Neoplasm; D051381:Rats; D006163:Ribonuclease T1; D012260:Ribonucleases; D012261:Ribonucleoproteins
chemical_list: D009843:Oligoribonucleotides; D012334:RNA, Neoplasm; D012261:Ribonucleoproteins; D012260:Ribonucleases; D006163:Ribonuclease T1